Update 1.2: BIND Check Plugin for Nagios

Update: I fixed a small, but nerving bug which is described further in this article. I also fixed the code below, means you can safely copy’n'paste it from this article as well.

I just made an update to the check_bind.sh script. It (hopefully without major bugs) now supports BIND 9.3 and 9.5 or greater as well. More of this and a few other improvements within the changelog.

Please note that I didn’t invest much time into testing yet. It works for me under Gentoo on different hosts via BIND 9.4 and BIND 9.6 without problems and on a Debian Lenny machine with BIND 9.5 as well. Please let me know if something doesn’t work for you and I try to improve the script to your needs. Thanks so far for the feedback!

Changelog

The plugin now supports BIND versions 9.3 and 9.5+.
The named.stats file is now initially parsed via awk and the excerpts are being copied to a temp directory for further use instead of frequently tail’ing the named.stats
The temporary directory is configurable via -t/–path-tmp as well
The path to the rndc binary is now configurable via -r/–path-rndc
You’re now able to deactivate the pid check via -N/–no-pid-check

The Script

As always the script is downloadable via NagiosExchange, from my public svn or directly with the nice and shiny copy’n'paste way from the codebox below.

user@host ~ $ svn co https://svn.matejunkie.com/svn/nagios-plugins/stable/check_bind/ check_bind/

#!/bin/sh
 
#   This program is free software; you can redistribute it and/or modify
#   it under the terms of the GNU General Public License as published by
#   the Free Software Foundation; either version 2 of the License, or
#   (at your option) any later version.
#
#   This program is distributed in the hope that it will be useful,
#   but WITHOUT ANY WARRANTY; without even the implied warranty of
#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#   GNU General Public License for more details.
#
#   You should have received a copy of the GNU General Public License
#   along with this program; if not, write to the Free Software
#   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 
PROGNAME=`basename $0`
VERSION="Version 1.2,"
AUTHOR="2009, Mike Adolphs (http://www.matejunkie.com/)"
 
ST_OK=0
ST_WR=1
ST_CR=2
ST_UK=3
path_pid="/var/run/named"
name_pid="named.pid"
path_rndc="/usr/sbin"
path_stats="/var/bind"
path_tmp="/tmp"
version=9.4
pid_check=1
 
print_version() {
    echo "$VERSION $AUTHOR"
}
 
print_help() {
    print_version $PROGNAME $VERSION
    echo ""
    echo "$PROGNAME is a Nagios plugin to check the bind daemon whether it's"
    echo "running via its pid file and then gets the statistics via rndc stats."
    echo "The user that run the script needs the ability to 'sudo rndc stats'!"
    echo "The timeframe in which the rndc stats output is updated is controlled"
    echo "by the check interval. The output shows amount of requests of various"
    echo "types occured during the last check interval."
    echo "The script itself is written sh-compliant and free software under the"
    echo "terms of the GPLv2 (or later)."
    echo ""
    echo "$PROGNAME -p/--path_pid /var/run/named -n/--name_pid named.pid"
    echo "  -r/--path-rndc /usr/sbin -s/--path-stats /var/bind"
    echo "  -V/--bind-version 9.3/9.4/9.5 -N"
    echo ""
    echo "Options:"
    echo "  -p/--path-pid)"
    echo "     Path where the pid file for bind is stored. You might need to"
    echo "     alter this to your distribution's way of dealing with pid files."
    echo "     Default is: /var/run/named"
    echo "  -n/--name_pid)"
    echo "     Name of the pid file. Default is: named.pid"
    echo "  -r/--path-rndc)"
    echo "     Path where the rndc binary is located. Default is: /usr/sbin"
    echo "  -s/--path-stats)"
    echo "     Path where the named.stats file is stored. Default is:"
    echo "     /var/bind"
    echo "  -t/--path-tmp)"
    echo "     Path where the temporary named.stats excerpt is being stored."
    echo "     Default is: /tmp"
    echo "  -V/--bind-version)"
    echo "     Specifies the bind version you're running. Currently there's"
    echo "     BIND 9.3, 9.4 and 9.5 supported. Default is: 9.4"
    echo "  -N/--no-pid-check)"
    echo "     If you don't want that the script checks for the pid file,"
    echo "     use this option. Default is: off"
    exit $ST_UK
}
 
while test -n "$1"; do
    case "$1" in
        -help|-h)
            print_help
            exit $ST_UK
            ;;
        --version|-v)
            print_version $PROGNAME $VERSION
            exit $ST_UK
            ;;
        --path-pid|-p)
            path_pid=$2
            shift
            ;;
        --name-pid|-n)
            name_pid=$2
            shift
            ;;
        --path-rndc|-r)
            path_rndc=$2
            shift
            ;;
        --path-stats|-s)
            path_stats=$2
            shift
            ;;
        --path-tmp|-t)
            path_tmp=$2
            shift
            ;;
        --bind-version|-V)
            version=$2
            shift
            ;;
        --no-check-pid|-N)
            pid_check=0
            ;;
        *)
            echo "Unknown argument: $1"
            print_help
            exit $ST_UK
            ;;
    esac
    shift
done
 
check_pid() {
    if [ -f "$path_pid/$name_pid" ]
    then
        retval=0
    else
        retval=1
    fi
}
 
trigger_stats() {
    sudo $path_rndc/rndc stats
}
 
copy_to_tmp() {
    tac $path_stats/named.stats | awk '/--- \([0-9]*\)/{p=1} p{print} /\+\+\+ \([0-9]*\)/{p=0;if (count++==1) exit}' > $path_tmp/named.stats.tmp
}
 
get_vals() {
    case ${version} in
        9.3)
            succ_1st=`cat $path_tmp/named.stats.tmp | grep -m1 '^success [0-9]*' | sort -n | awk '{print $2}'`
            succ_2nd=`cat $path_tmp/named.stats.tmp | grep -o '^success [0-9]*' | sort -n | grep -m1 '^success [0-9]*' | awk '{print $2}'`
            ref_1st=`cat $path_tmp/named.stats.tmp | grep -m1 '^referral [0-9]*' | sort -n | awk '{print $2}'`
            ref_2nd=`cat $path_tmp/named.stats.tmp | grep -o '^referral [0-9]*' | sort -n | grep -m1 '^referral [0-9]*' | awk '{print $2}'`
            nxrr_1st=`cat $path_tmp/named.stats.tmp | grep -m1 '^nxrrset [0-9]*' | sort -n | awk '{print $2}'`
            nxrr_2nd=`cat $path_tmp/named.stats.tmp | grep -o '^nxrrset [0-9]*' | sort -n | grep -m1 '^nxrrset [0-9]*' | awk '{print $2}'`
            nxdom_1st=`cat $path_tmp/named.stats.tmp | grep -m1 '^nxdomain [0-9]*' | sort -n | awk '{print $2}'`
            nxdom_2nd=`cat $path_tmp/named.stats.tmp | grep -o '^nxdomain [0-9]*' | sort -n | grep -m1 '^nxdomain [0-9]*' | awk '{print $2}'`
            rec_1st=`cat $path_tmp/named.stats.tmp | grep -m1 '^recursion [0-9]*' | sort -n | awk '{print $2}'`
            rec_2nd=`cat $path_tmp/named.stats.tmp | grep -o '^recursion [0-9]*' | sort -n | grep -m1 '^recursion [0-9]*' | awk '{print $2}'`
            fail_1st=`cat $path_tmp/named.stats.tmp | grep -m1 '^failure [0-9]*' | sort -n | awk '{print $2}'`
            fail_2nd=`cat $path_tmp/named.stats.tmp | grep -o '^failure [0-9]*' | sort -n | grep -m1 '^failure [0-9]*' | awk '{print $2}'`
            ;;
        9.4)
            succ_1st=`cat $path_tmp/named.stats.tmp | grep -m1 '^success [0-9]*' | sort -n | awk '{print $2}'`
            succ_2nd=`cat $path_tmp/named.stats.tmp | grep -o '^success [0-9]*' | sort -n | grep -m1 '^success [0-9]*' | awk '{print $2}'`
            ref_1st=`cat $path_tmp/named.stats.tmp | grep -m1 '^referral [0-9]*' | sort -n | awk '{print $2}'`
            ref_2nd=`cat $path_tmp/named.stats.tmp | grep -o '^referral [0-9]*' | sort -n | grep -m1 '^referral [0-9]*' | awk '{print $2}'`
            nxrr_1st=`cat $path_tmp/named.stats.tmp | grep -m1 '^nxrrset [0-9]*' | sort -n | awk '{print $2}'`
            nxrr_2nd=`cat $path_tmp/named.stats.tmp | grep -o '^nxrrset [0-9]*' | sort -n | grep -m1 '^nxrrset [0-9]*' | awk '{print $2}'`
            nxdom_1st=`cat $path_tmp/named.stats.tmp | grep -m1 '^nxdomain [0-9]*' | sort -n | awk '{print $2}'`
            nxdom_2nd=`cat $path_tmp/named.stats.tmp | grep -o '^nxdomain [0-9]*' | sort -n | grep -m1 '^nxdomain [0-9]*' | awk '{print $2}'`
            rec_1st=`cat $path_tmp/named.stats.tmp | grep -m1 '^recursion [0-9]*' | sort -n | awk '{print $2}'`
            rec_2nd=`cat $path_tmp/named.stats.tmp | grep -o '^recursion [0-9]*' | sort -n | grep -m1 '^recursion [0-9]*' | awk '{print $2}'`
            fail_1st=`cat $path_tmp/named.stats.tmp | grep -m1 '^failure [0-9]*' | sort -n | awk '{print $2}'`
            fail_2nd=`cat $path_tmp/named.stats.tmp | grep -o '^failure [0-9]*' | sort -n | grep -m1 '^failure [0-9]*' | awk '{print $2}'`
            dup_1st=`cat $path_tmp/named.stats.tmp | grep -m1 '^duplicate [0-9]*' | sort -n | awk '{print $2}'`
            dup_2nd=`cat $path_tmp/named.stats.tmp | grep -o '^duplicate [0-9]*' | sort -n | grep -m1 '^duplicate [0-9]*' | awk '{print $2}'`
            drop_1st=`cat $path_tmp/named.stats.tmp | grep -m1 '^dropped [0-9]*' | sort -n | awk '{print $2}'`
            drop_2nd=`cat $path_tmp/named.stats.tmp | grep -o '^dropped [0-9]*' | sort -n | grep -m1 '^dropped [0-9]*' | awk '{print $2}'`
            ;;
        9.5)
            succ_1st=`grep 'resulted in successful answer' $path_tmp/named.stats.tmp | awk '{ print $1 }' | grep -m1 ''`
            succ_2nd=`grep 'resulted in successful answer' $path_tmp/named.stats.tmp | awk '{ print $1 }' | sort -n | grep -m1 ''`
            ref_1st=`grep 'resulted in referral' $path_tmp/named.stats.tmp | awk '{ print $1 }' | grep -m1 ''`
            ref_2nd=`grep 'resulted in referral' $path_tmp/named.stats.tmp | awk '{ print $1 }' | sort -n | grep -m1 ''`
            nxrr_1st=`grep 'resulted in nxrrset' $path_tmp/named.stats.tmp | awk '{ print $1 }' | grep -m1 ''`
            nxrr_2nd=`grep 'resulted in nxrrset' $path_tmp/named.stats.tmp | awk '{ print $1 }' | sort -n | grep -m1 ''`
            nxdom_1st=`grep 'resulted in NXDOMAIN' $path_tmp/named.stats.tmp | awk '{ print $1 }' | grep -m1 ''`
            nxdom_2nd=`grep 'resulted in NXDOMAIN' $path_tmp/named.stats.tmp | awk '{ print $1 }' | sort -n | grep -m1 ''`
            rec_1st=`grep 'caused recursion' $path_tmp/named.stats.tmp | awk '{ print $1 }' | grep -m1 ''`
            rec_2nd=`grep 'caused recursion' $path_tmp/named.stats.tmp | awk '{ print $1 }' | sort -n | grep -m1 ''`
            fail_1st=`grep 'resulted in SERVFAIL' $path_tmp/named.stats.tmp | awk '{ print $1 }' | grep -m1 ''`
            fail_2nd=`grep 'resulted in SERVFAIL' $path_tmp/named.stats.tmp | awk '{ print $1 }' | sort -n | grep -m1 ''`
            dup_1st=`grep 'duplicate queries received' $path_tmp/named.stats.tmp | awk '{ print $1 }' | grep -m1 ''`
            dup_2nd=`grep 'duplicate queries received' $path_tmp/named.stats.tmp | awk '{ print $1 }' | sort -n | grep -m1 ''`
            ;;
    esac
 
    if [ "$succ_1st" == '' ]
    then
        success=0
    else
        success=`expr $succ_1st - $succ_2nd`
    fi
    if [ "$ref_1st" == '' ]
    then
        referral=0
    else
        referral=`expr $ref_1st - $ref_2nd`
    fi
    if [ "$nxrr_1st" == '' ]
    then
        nxrrset=0
    else
        nxrrset=`expr $nxrr_1st - $nxrr_2nd`
    fi
    if [ "$nxdom_1st" == '' ]
    then
        nxdomain=0
    else
        nxdomain=`expr $nxdom_1st - $nxdom_2nd`
    fi
    if [ "$rec_1st" == '' ]
    then
        recursion=0
    else
        recursion=`expr $rec_1st - $rec_2nd`
    fi
    if [ "$fail_1st" == '' ]
    then
        failure=0
    else
        failure=`expr $fail_1st - $fail_2nd`
    fi
    if [ "$dup_1st" == '' ]
    then
        duplicate=0
    else
        duplicate=`expr $dup_1st - $dup_2nd`
    fi
    if [ "$drop_1st" == '' ]
    then
        dropped=0
    else
        dropped=`expr $drop_1st - $drop_2nd`
    fi
}
 
get_perfdata() {
    case ${version} in
        9.3)
            perfdata=`echo "'success'=$success 'referral'=$referral 'nxrrset'=$nxrrset 'nxdomain'=$nxdomain 'recursion'=$recursion 'failure'=$failure"`
            ;;
        *)
            perfdata=`echo "'success'=$success 'referral'=$referral 'nxrrset'=$nxrrset 'nxdomain'=$nxdomain 'recursion'=$recursion 'failure'=$failure 'duplicate'=$duplicate 'dropped'=$dropped"`
            ;;
    esac
}
 
if [ ${pid_check} == 1 ]
then
    check_pid
    if [ "$retval" = 1 ]
    then
        echo "There's no pid file for bind9. Is it actually running?"
        exit $ST_CR
    fi
fi
 
trigger_stats
copy_to_tmp
get_vals
get_perfdata
 
echo "Bind9 is running. $success successfull requests, $referral referrals, $nxdomain nxdomains since last check. | $perfdata"
exit $ST_OK

The License

As always this little script is ment to be sh-compliant and released under the terms of the GPL Version 2 only. Feel free to subscribe via rss to get updates on this one. More options will be added in the future.

Share and Enjoy:

Tagged: BIND, dns, gplv2, linux, nagios, network monitoring, open source, plugin, shell scripting, sysadmin

On 05.03.09 Bind check plugin for Nagios | Matejunkie said:

[...] 05.03.09 Update 1.2: BIND Check Plugin for Nagios | Matejunkie [...]

On 05.18.09 Gareth Fletcher said:

Hey hmm this still doesn’t seem to work on my Bind 9.5 install, the perfdata is blank. Thanks for the plugin though

On 05.19.09 Mike said:

Hi Gareth,

in my productive environment where I’m using a BIND 9.5 server, it’s just fine. How did you call the script exactly? It should be run for Bind 9.5 like the following since 9.4 is the default value: ./check_bind.sh -V 9.5
Furthermore is the Nagios user allowed via /etc/sudoers to run /usr/sbin/rndc stats? Please also check whether the rndc binary resides in /usr/sbin and not in a different directory. That may vary from one distribution to another. So it is for the named.stats file which is written by the rndc binary when one’s calling ‘rndc stats’. You may also need to adjust those path variables and named.stats variable according to your distribution.

Hope this helps to get the plugin running. If not, you’re welcome to provide more information, for example the output of an “sh -x check_bind.sh -V 9.5″ via mail to mike@matejunkie.com or an example of your named.stats file. I’ll try to provide more help then since it makes it a lot easier to debug.

On 07.17.09 n00dl3s said:

Great script, but two small additions from my side:

- there is a typo on line 151: it should read “>” but in the code above the “>” is in HTML markup “>” which is not helpful when copy and pasting…

- you should definitely include a warning in the comments or even a check in the script itself that “zone statistics no;” has to be set in the bind9 config (on an old Debian etch system this parameter is in /etc/bind/named.conf.options). Otherwise the named.stats file contains separate statistics for all the zones on the name server and subsequently the awk part will find very strange numbers… (I don’t know though what the default setting was, so it might not be a problem for most people…)

But otherwise: Thank you very much for this plugin!

On 07.29.09 Mike Adolphs said:

Thanks n00dl3s for mentioning the bug. I’ve just corrected it in the article. And thank you for the additional information on “zone statistics no”, I’ll include this as well!
And sorry for the late answer, … I’m currently administrating about 350 servers on my own since everyone else is on holiday. That makes time a valuable resource.

Matejunkie

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